#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <stdlib.h>
#include <unistd.h>

int main()
{
    close(0);//关闭0号文件描述符

    umask(0);
    int fd1 = open("log1.txt", O_CREAT|O_WRONLY|O_TRUNC,0666);
    int fd2 = open("log2.txt", O_CREAT|O_WRONLY|O_TRUNC,0666);
    int fd3 = open("log3.txt", O_CREAT|O_WRONLY|O_TRUNC,0666);
    int fd4 = open("log4.txt", O_CREAT|O_WRONLY|O_TRUNC,0666);
    
    if(fd1<0) exit(1);
    if(fd2<0) exit(1);
    if(fd3<0) exit(1);
    if(fd4<0) exit(1);

    //printf("stdin = %d\n",stdin->_fileno);
    //printf("stdout = %d\n",stdout->_fileno);
    //printf("stderr = %d\n",stderr->_fileno);
    
    printf("fd1 = %d\n",fd1);
    printf("fd2 = %d\n",fd2);
    printf("fd3 = %d\n",fd3);
    printf("fd4 = %d\n",fd4);



    close(fd1);
    close(fd2);
    close(fd3);
    close(fd4);
    return 0;
}
